Parametric investigation of canyon shape effects on the seismic response of 3D concrete gravity dam model

In this study, the three-dimensional seismic response of Pine Flat concrete gravity dam is investigated. For this purpose, two- and three-dimensional nonlinear analyses are carried out based on the finite element method. The effects of canyon shape variation on the seismic response of the dam are evaluated, and different components of a seismic record are considered to assess the dominance of each earthquake component on the structural behavior. Two sources of nonlinearity are taken into account including material and geometric nonlinearities. As geometric nonlinearity, vertical contraction joints are considered within the dam body, and the results are compared with integrated models. It is concluded that stream component of earthquake record plays an important role on the crest displacement. Assuming two- and three-dimensional dam-reservoir-foundation coupled system may lead to partly different results. It is finally observed that, although utilizing contraction joints increases the amount of compressive stresses in the allowable range, but the tensile damages imposed to the dam body may encounter a significant decrease.